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EndsemNov 20242019 patternBE E&TC

Fiber Optic Communication (FOC) SPPU Endsem Question Paper Nov 2024

All 8 questions from this SPPU endsem paper, as printed. Read them here or open the PDF.

Open the PDFMost repeated FOC questions
Subject code
404190
Pattern
2019 pattern
Exam
Endsem
Session
Nov 2024
Max. marks
70
Time
2½ Hours
Semester
VIII
Paper code
[6354]-541

Printed for: B.E. (E&TC)

Instructions to the candidates

  1. Answer Q.1 or Q.2, Q.3 or Q.4, Q.5 or Q.6, Q.7 or Q.8
  2. Figures to the right indicate full marks.
  3. Assume suitable data if necessary.

Questions

  1. Q1

    1. a)

      What are the requirements of material selection for photodetectors.

      [5]
    2. b)

      Draw the structure of APD and explain its working.List its advantages and drawbacks.

      [6]
    3. c)

      Explain different types of noise in the receiver.

      [6]

  2. Q2

    1. a)

      Draw structure of p-i-n photodiode and explain its operation in brief. Plot the responsivity curve as function of wavelength for p-i-n photodiodes.

      [6]
    2. b)

      A given APD has a quantum efficiency of 65% at a wavelength of 900 nm.Suppose 0.5 micro watt of optical power produces a multiplied photocurrent of 10 micro A.Find multiplication factor.

      [6]
    3. c)

      Explain receiver structure in detail.

      [5]

  3. Q3

    1. a)

      Let the data rate of 20mb/s and BER of 10-9. For the receiver PIN photodiode operating at 850 nm, the required receiver input signal is -42dBm .The LED is used as a source can couple 50uW(-l3dBm) average optical power into a fiber flylead with a 50 um core diameter. Assume 1dB loss occurs when the fiber flylead is connected to the cable and another 1dB connector loss at the cable-photo detector interface. System margin of 6dB.Let attenuation per km is 3.5dB/ km. Estimate link length.

      Also asked:Nov 2023

      [7]
    2. b)

      Write short note on optical coupler, circulator and isolator.

      Also asked:Nov 2025

      [6]
    3. c)

      Illustrate fiber grating with the help of a neat diagram. 2

      [5]

  4. Q4

    1. a)

      An optical fiber transmission system is to be designed to operate on 8km length without repeaters. The rise time of the chosen components are source LED : 8ns, Fiber cable: intermodal : 5ns/km, Intramodal: 1ns/km, Detector PIN :6ns Estimate maximum bit rate that may be achieved on the link when using NRZ and RZ formats.

      Also asked:May 2025

      [6]
    2. b)

      Enlist types of optical amplifiers.Explain EDFA in detail.

      [6]
    3. c)

      Illustrate the significance of WDM components with suitable block diagram. List the formulas for fused-Biconical coupler.

      [6]

  5. Q5

    1. a)

      Define network topology. State and explain types of network topologies with suitable diagrams.

      Also asked:May 2025

      [5]
    2. b)

      What is Fiber Distributed Data Interface (FDDI) and its features?Explain with diagram FDDI with respect to ring structure, Reference Model, frame and topology used.

      [8]
    3. c)

      Write short note on Active Optical network and Passive optical network.

      Also asked:Nov 2025 ·May 2025

      [5]

  6. Q6

    1. a)

      Define Optical Network. Explain the term optical node & light path with a suitable diagram relative to optical network.

      Also asked:May 2025 ·May 2024

      [5]
    2. b)

      What is FTTX? What are the different categories of FTTX?Explain FTTX with respect to architecture.

      Also asked:May 2025 ·May 2024

      [6]
    3. c)

      Explain SONET with the help of structure,state advantages and applications.

      Also asked:Nov 2023

      [7]

  7. Q7

    1. a)

      Describe OTDR with the help of a block diagram. Explain a typical trace of losses on OTDR.

      [7]
    2. b)

      Explain intermodal dispersion measurement technique.

      Also asked:Nov 2023

      [5]
    3. c)

      Draw and explain EYE diagram measurement set up.

      [5]

  8. Q8

    1. a)

      What is attenuation?Describe with necessary experimental arrangement for the measurement of the signal attenuation in an optical fiber by cutback technique.

      Also asked:May 2025

      [7]
    2. b)

      Consider a long optical fiber with core refractive index n 1 =1.460.Suppose that an engineer uses OTDR to locate a break in the fiber.If the break is located 15km away,What is the return time of an OTDR test pulse?

      [4]
    3. c)

      List the widely used optical measuring instruments and explain any three measuring instruments in detail. 

      [6]